Some pornographic films use an artificial semen substitute to simulate or enhance creampie shots. The term bondage describes the practice of Physical restraining. Barebacking usually refers to a conscious and deliberate choice to forgo condoms. Diaper fetishism, nappy young gay porn fetishism or diaperism, is a sexual fetish in which a person feels a desire to wear or use diapers. The name was coined from the title of the controversial book. The term sadomasochism is derived from the words sadism and masochism . Sexual relations between women have been illustrated as well as narrated, but much of the written material from the early modern period has been destroyed. Lolita pornography features women who are 18 years old or slightly older, who pretend to be underage teen girls. Some are aroused from wetting their diapers, others like messing their diapers. Internationally, hentai is a catch-all term to describe a genre of anime and manga pornography. In the West, masturbation in private or with a partner is generally considered a normal and healthy part of sexual enjoyment. Oral sex pornography frequently features a person performing fellatio, and less frequently cunnilingus. Solo performances in gay pornography have been described in 1985 as either or both active and/or passive , whereas female solo performances hentai sex are said to be exclusively passive . Double penetration of the vagina, anus and mouth, can involve: Simultaneous penetration of the anus by two penises or other objects. The first explicit pegging scene is believed to have been in the 1975 pornographic film The Opening of milf xxx Misty Beethoven. In S/M, the Sadist is usually the Top and the Masochist the Bottom, but these roles are frequently more complicated or jumbled . Commenting on why there are not as many female macrophiles, psychologist Helen Friedman theorized that because women in most societies already view men as dominant and powerful, there no need for them to fantasize about it. In Japanese, this natural-fibre rope is known as asanawa; the Japanese vocabulary does not make a distinction between hemp and jute.